Capacitance Characteristic Analysis hauv EMC Tsim Kev Siv Hluav Taws Xob
Ntau tus neeg tsim hluav taws xob paub lub luag haujlwm ntawm lim capacitors hauv cov khoom siv hluav taws xob, tab sis cov khoom siv lim dej siv ntawm cov khoom siv hluav taws xob hloov pauv txawv ntawm cov lim capacitors siv nyob rau hauv lub hwj chim zaus circuits. Electrolytic capacitors, zaus ntawm lub zog pulsating ntawm nws tsuas yog 100 Hz, thiab lub sijhawm them nqi thiab tawm yog nyob ntawm qhov kev txiav txim ntawm milliseconds. Yuav kom tau txais me me pulsation coefficient, qhov yuav tsum tau muaj peev xwm yog siab li ntau pua txhiab microfarads. Yog li ntawd, zoo tib yam txhuas electrolytic capacitors feem ntau yog siv rau tsawg zaus. Lub hom phiaj yog tsuas yog ua kom lub capacitance. Lub capacitance, poob tangent thiab to tam sim no ntawm lub capacitor yog qhov tseem ceeb tsis tau txheeb xyuas nws qhov zoo thiab qhov tsis zoo.
Raws li electrolytic capacitor rau cov zis lim hauv kev hloov pauv tswj fais fab, qhov zaus ntawm sawtooth yoj voltage ntawm nws yog siab li kaum ntawm kilohertz, lossis txawm kaum ntawm megahertz. Nws cov kev xav tau txawv ntawm cov hauv kev siv tsawg zaus. Capacitance tsis yog lub ntsiab qhia. Qhov zoo lossis qhov tsis zoo yog nws tus yam ntxwv impedance-zaus zaus, uas yuav tsum muaj qhov impedance qis hauv kev ua haujlwm zaus ntawm kev hloov hluav taws xob tswj hluav taws xob. , Nws kuj tuaj yeem muaj cov nyhuv lim dej zoo. Feem ntau, cov khoom siv hluav taws xob zoo tib yam siv rau cov zaus qis yog nyob ib ncig ntawm 10 kHz, thiab lawv cov impedance pib tshwm inductive, uas tsis tuaj yeem ua tau raws li qhov yuav tsum tau muaj ntawm cov khoom siv hluav taws xob hloov.
Lub high-frequency txhuas electrolytic capacitor nplooj siab rau lub switching fais fab mov muaj plaub terminals. Ob qhov kawg ntawm daim ntawv zoo txhuas yog feem ntau kos tawm raws li qhov zoo electrode ntawm lub capacitor, thiab ob qhov kawg ntawm daim ntawv tsis zoo txhuas kuj tau kos tawm raws li qhov tsis zoo electrode. Tam sim no ntawm cov tswj fais fab mov ntws los ntawm ib qho zoo kawg ntawm plaub-terminal capacitor, dhau los ntawm lub capacitor, thiab tom qab ntawd ntws los ntawm lwm qhov kawg mus rau lub load; Tam sim no rov qab los ntawm lub load kuj ntws los ntawm ib qho tsis zoo kawg ntawm lub capacitor, thiab ces ntws los ntawm lwm yam tsis zoo kawg mus rau lub hwj chim mov tsis zoo davhlau ya nyob twg.
Vim hais tias plaub lub davhlau ya nyob twg capacitor muaj cov yam ntxwv siab zaus, nws muab ib qho txiaj ntsig zoo heev rau kev txo cov pulsating tivthaiv ntawm cov zis hluav taws xob thiab suppressing lub suab nrov nrov nrov.
High-frequency aluminium electrolytic capacitors kuj muaj ntau daim ntawv, uas faib cov txhuas ntawv ci rau hauv ob peb ntu luv thiab txuas rau lawv nyob rau tib lub sijhawm nrog ntau yam ua rau txo cov kev tiv thaiv tiv thaiv hauv capacitive reactance. Nyob rau tib lub sijhawm, nws siv cov ntaub ntawv uas tsis tshua muaj siab thiab siv cov ntsia hlau ua cov hlau lead terminals los txhim kho lub peev xwm ntawm lub capacitor kom tiv taus cov dej loj.
Laminated capacitors tseem hu ua non-inductive capacitor. Feem ntau, cov cores ntawm electrolytic capacitors yog dov rau hauv cylindrical duab, thiab qhov sib npaug series inductance yog loj; cov qauv ntawm laminated capacitors zoo ib yam li cov phau ntawv. Offset, yog li txo tus nqi ntawm cov inductance thiab muaj cov yam ntxwv zoo dua qub, lub capacitor hom no feem ntau ua rau hauv cov duab plaub, uas yooj yim kho, thiab tuaj yeem tsim nyog txo qhov ntim ntawm lub tshuab.
Tsis tas li ntawd, muaj plaub-terminal laminated high-frequency electrolytic capacitor uas ua ke nrog plaub-terminal thiab laminated daim hlau, uas muab cov txiaj ntsig zoo ntawm ob qho tib si, thiab muaj cov yam ntxwv zoo dua.
